How Do RV Refrigerators Work?
There are three types of RV refrigerators commonly in use: residential, two-way and three-way refrigerators.
Residential refrigerators in RVs are relatively new; these are like the refrigerator in your home, and will only work on AC electric. This means you will need to stay at an RV park and plug into the power there, or, use your generator to keep the refrigerator going.
Two-way and three-way RV refrigerators are more common, with two-way refrigerators as the most common. A two-way RV refrigerator runs on both AC electric as well as propane, and a three-way runs on AC and DC electric, and propane. There will be a switch on the refrigerator to switch it between the different power sources. There may also be an “auto” setting to automatically switch it between AC and propane.
You may be wondering, how does a refrigerator run on propane? It’s a complicated subject, but it involves using the cooling action of condensation. A propane refrigerator has a network of chambers and tubes containing water, ammonia and hydrogen gas. Propane is used to boil a chamber with a mixture of water and ammonia. The ammonia gas rises up into another chamber, where it cools back into a liquid. It then goes into a chamber, with hydrogen gas, and when the ammonia mixes with hydrogen gas, it produces its cooling action.
There is a louvered hatch on the outside of a propane refrigerator, and if you take it off, you will feel the heat from the propane boiling the ammonia and water. The important thing to remember about a propane refrigerator is, you need to turn it off when you are at a gas station. The pilot light can come on, and having an open flame at a gas station is both dangerous and illegal. When you are driving, either switch the refrigerator to DC power if you can or simply turn it off. There is a button on the refrigerator to turn it off. Your food will be fine for a few hours while you drive if the refrigerator is turned off.
How Do RV Tank Sensors Work?
Inside of the RV fresh water, gray and black tanks are sensors to indicate how full the tank is. These are electronically connected to a control panel inside the RV; you can push a button to see how full each tank is. The levels usually go full, ¾, ½ and ¼ full and empty.
Unfortunately, the sensors inside of the gray and black tanks can get dirty and you may not get an accurate reading. You can buy sensor cleaners at an RV store as well as Walmart; be sure to follow the directions. It’s also a good idea to know how big your tanks are, and to keep track of how many showers you take, how many toilet flushes and when was the last time you emptied the tanks. Generally, unless the tank sensors are clean, they may only give you an approximate reading.